Levels of PCBs, methyl mercury and dioxins in many Great Lakes fish, such as salmon, rainbow trout, walleye, pike and lake trout are too high for human consumption, according to a new report called Up to the Gills: Pollution in Great Lakes Fish, by Environmental Defence, a Canadian conservation group. Despite some falls in contamination levels in certain parts of the Great Lakes, the report states that serious problems still exist and seems to be getting worse.

The number of public health warnings regarding the consumption of fish from Lake Ontario has increased significantly over the last few years, where eight categories of fish became more contaminated between 2005 and 2007 and only one category improved. Of concern are also Lake Huron, Lake Erie and even supposedly clean Lake Superior. The report said that such is the extent of the problem “that human health is threatened”.

The report compared the fish advisories published by the Ontario Ministry of the Environment for four species of fish in 13 locations across the Great Lakes in 2005 and 2007. Many categories of fish are now somewhat or completely unfit for human consumption while others are becoming so.

The report estimates that approximately 50,000 tons of industrial pollutants are pouring into the Great Lakes annually.

Aaron Freeman, Policy Director of Environmental Defence, said “While fish remains a healthy choice for consumers, toxic contamination levels suggest that we are still treating the Great Lakes as a toxic waste dump. We are clearly not doing enough to protect this vital ecosystem. We need stronger pollution regulations and a real plan from the federal and provincial governments to clean up the Lakes.”

The main pollutants that cause public warnings are:
— Mercury
— PCBs
— Pesticides
— Dioxins
— Furans

These chemicals can damage our nervous, respiratory and immune systems – they are also carcinogenic. The larger the fish the more severe the public advisory tends to be – larger fish are older and have been accumulating toxins for longer. However, severe consumption advisories have been issued for even small fishes in Lake Ontario.

About 5 million people go to the Great Lakes for its fishing each year, commercial and sport fishing is worth $3.5 billion dollars a year.

The report advises that authorities improve the information used in fish advisories, enhance the delivery of fish advisories to high risk groups, and prevent fish contamination advisories by reducing pollution from industry, sewage systems, agriculture and urban runoff.

Up to the Gills: Pollution in Great Lakes Fish(pdf)

www.environmentaldefence.ca

Written by: Christian Nordqvist
Editor: Medical News Today